Software giants including Google and Amazon are interested in ramping up
hardware to boost customer loyalty and to extend control over their software
services and the revenues that flow from them. That is heightening their
collision course with Apple, which is responding by building more of its own
software to make its devices stand out.

Google, with the $12.5 billion purchase of Motorola Mobility under its belt,
plans to use the phone maker to release new Android devices to help knock
Apple's iPhone off its perch. And Amazon, which has upped the ante in the tablet
wars with the Kindle Fire, has also been testing its own phone.

Meanwhile, all four companies see search as a big opportunity for retaining
and profiting off customers. While Google's paradigm of typing queries in a
search box has prevailed for years, now its rivals want to undercut the
Web-search giant through mobile search on smartphones and other devices, and a
slew of search services that allow recommendations from friends.